Gas Chromatographic Separation of Metal Halides by Inorganic Fused Salt Substrates

Abstract

place down the column. However, during analysis of the mixture, an initial flow rate decrease takes place as a result of adsorption of carbon monoxide. The normal gas peak obtained for hydrogen in the mixture will be different from that obtained in the calibration, as the column conditions are completely different (5). Such interference has already been reported for another system (6). It occurs regardless of the method used for peak measurement, as both peak height and area are affected by velocity changes (<?).For optimum operation with thermal conductivity detectors, pressure changes should be kept small. Such changes augment flowr changes and increase errors from this source.Measures for remedying base line instability-which do not minimize pressure changes are satisfactory for the first type of interference, but conditions for analysis may still be far from optimum.Errors caused by the second (veloc-

Molten Salt Mixtures as Liquid Phases in Gas Chromatography

“…Nonvolatile, or low-volatility compounds, have also been analyzed, following conversion to more volatile derivatives (1,5,7). New methods are herein proposed for analyzing complex mixtures of nonvolatile sulfonic acids and salts by gas chromatography of volatile derivatives.…”

“…has been suggested by Phillips (9). Juvet and Wachi (7) have reported partial separations of Volatile transition metal chlorides on inorganic salt eutectics. However, no results on the use of molten salts to separate organic compounds appear to have been reported to date.…”

Molten organic salt phase for gas-liquid chromatography

“…Houghton (8) and Haarhoff et al (9) have obtained analytical equations of peak profiles by solving the partial differential equations of chromatography when the deviation of the isotherm from linearity is small. These expressions are too complex to be handled in practice and, therefore, De Clerk and Buys (10)(11)(12)(13) and Yamaoka and Nakagawa (14) have developed expressions for the statistical moments with a nonlinear distribution isotherm.…”

“…Saturated solutions of silver nitrate in ethylene glycol, glycerol, and benzyl cyanide have been used as selective phases for the separation of unsaturated compounds by charge transfer interactions (10)(11)(12). Fused inorganic salt systems have been used to separate mixtures of various inorganic compounds (1,13,14). In these systems, separations were achieved by selective complexation of the solutes within the molten salt stationary phase.…”

Gas chromatography: Basic principles and new developments

“…Organic materials (e.g., silicones, Apiezon greases, asphaltenes, etc.) are useful to about 350°( 51)\ above this temperature one must resort to inorganic salt eutectics (52). Some work has already been done up to 500-000°, and 1000°seems attainable shortly.…”